This application is to test the feasibility of assessing the role of lipid bilayer peroxidation in functionally inactivating bovine rhodopsin, relative to its role in triggering visual transduction. This will be accomplished by characterizing the groups in rhodopsin which undergo modification and evaluating the level of light stimulated cGMP activity induced by these modified rhodopsins. Initial experiments to test the hypothesis that a major contributing factor in photoreceptor degeneration under conditions which promote lipid peroxidation, is the funcitonal degradation of the proteins involved in visual transduction, would be undertaken during this project period.